Symptoms of a blown/leaking intake gasket?

Discussion in 'Fox 5.0 Mustang Tech' started by 85_SS_302_Coupe, May 18, 2009.

  1. Yeah i forgot to mention that...i have always put them blue line side up anyways. I basically pissed away $30 just checking the gaskets :mad:
  2. Did you figgure this out yet?
  3. Hell no...still completely stumped. The intake gaskets were perfect but i replaced them anyways. I've been through the carb twice now, put it on another engine and it ran fine, and even put another carb on my engine with the same problems so now i KNOW it's not the carb. I've changed the fuel pump so i'm pretty sure it's not that (besides it doesn't take much fuel to keep it idling...and it drives like normal, just won't idle). I've swapped out the HEI module and the coil. The only thing left is the distributor but i can't see it being that when it drives just fine but won't idle. I'm close to saying screw it and ripping the whole engine apart until i find the problem.
  4. Did I miss the post that had the results of your using a vacuum gauge to get some vacuum readings?
  5. LOL, no you didn't miss it but now that i know for certain i have good intake gaskets, where could i possibly have a vacuum leak? Another thing i thought of is that if i did have a vacuum leak that was b ad enough to stall the car, wouldn't it effect drivability beyond the idle? This is the craziest part to me...if you drive the car it's like there's nothing wrong with pulls like crazy. It just won't idle.
  6. Carb cars have an entirely different set of things that can misbehave like metering jets and power valves that add extra gas above the idle range.
  7. Well the thing is, i've put my carb on another engine and it idled and ran fine, plus i've swapped on another carb onto my car and had the same idle problems. At this point i'm 100% sure it's not the carb and it's not fuel related, because when the car stalls you can take the sight plug out of the fuel bowl and it's full of gas so it's not starving out. This has to be ignition related...something causing it to stop firing.
  8. Well so far it turns out it was the distributor. Another guy mentioned that he had a similar problem with the weights in the distributor sticking causing it to add timing at idle, which in turn meant you couldn't lower the idle screw on the carb enough to compensate for it without going so low that it stalled the carb out. I have to assume this is what mine was doing because now it's idling at 900rpm just fine (so far). Everyone cross your fingers for me and hope it stays that way.